Skeletal Radiology最新文献

Objective: To analyze and quantify the change in United States of America Medicare reimbursement rates for the 30 most commonly performed spinal imaging procedures.

Materials and methods: The Physician Fee Schedule Look-Up Tool from the Centers for Medicare & Medicaid Services was utilized to find and extract the 28 most billed spinal imaging procedures. All data was adjusted for inflation and listed in 2020 US dollars. Percent change in reimbursement and Relative Value Units between 2005 and 2020, both unadjusted and adjusted, were calculated and compared. Additionally, percent change per year and compound annual growth rate were calculated and compared.

Results: After adjusting for inflation, the average reimbursement for all analyzed spinal imaging procedures between the years 2005 and 2020 decreased by 45.9%. The adjusted reimbursement rate for all procedures decreased at an average 4.3% per year and experienced an average compound annual growth rate (CAGR) of - 4.4%. Magnetic resonance imaging (MRI) had the most substantial adjusted decline of all imaging modalities at - 72.6%, whereas x-ray imaging had the smallest decline at - 27.33%. The average total RVUs per procedure decreased by 50.1%, from 7.96 to 3.97.

Conclusion: From the years 2005 to 2020, Medicare reimbursement significantly decreased for all advanced imaging modalities involving the most common spinal imaging procedures. Among all practices, imaging procedures may be experiencing some of the largest decreases from Medicare reimbursement cutbacks.

Objective: A fully automated laminar cartilage composition (MRI-based T2) analysis method was technically and clinically validated by comparing radiographically normal knees with (CL-JSN) and without contra-lateral joint space narrowing or other signs of radiographic osteoarthritis (OA, CL-noROA).

Materials and methods: 2D U-Nets were trained from manually segmented femorotibial cartilages (n = 72) from all 7 echoes (All_E), or from the 1st echo only (1^st_E) of multi-echo-spin-echo (MESE) MRIs acquired by the Osteoarthritis Initiative (OAI). Because of its greater accuracy, only the All_E U-Net was then applied to knees from the OAI healthy reference cohort (n = 10), CL-JSN (n = 39), and (1:1) matched CL-noROA knees (n = 39) that all had manual expert segmentation, and to 982 non-matched CL-noROA knees without expert segmentation.

Results: The agreement (Dice similarity coefficient) between automated vs. manual expert cartilage segmentation was between 0.82 ± 0.05/0.79 ± 0.06 (All_E/1^st_E) and 0.88 ± 0.03/0.88 ± 0.03 (All_E/1^st_E) across femorotibial cartilage plates. The deviation between automated vs. manually derived laminar T2 reached up to - 2.2 ± 2.6 ms/ + 4.1 ± 10.2 ms (All_E/1^st_E). The All_E U-Net showed a similar sensitivity to cross-sectional laminar T2 differences between CL-JSN and CL-noROA knees in the matched (Cohen's D ≤ 0.54) and the non-matched (D ≤ 0.54) comparison as the matched manual analyses (D ≤ 0.48). Longitudinally, the All_E U-Net also showed a similar sensitivity to CL-JSN vs. CS-noROA differences in the matched (D ≤ 0.51) and the non-matched (D ≤ 0.43) comparison as matched manual analyses (D ≤ 0.41).

Conclusion: The fully automated T2 analysis showed a high agreement, acceptable accuracy, and similar sensitivity to cross-sectional and longitudinal laminar T2 differences in an early OA model, compared with manual expert analysis.

Trial registration: Clinicaltrials.gov identification: NCT00080171.

The accessory anterolateral talar facet (AALTF) is an anatomical variation that broadens the apex of the lateral talar process. Studies have associated it with other tarsal coalitions as a cause of rigid painful flatfoot. However, a coalition of an AALTF has never been described before. With the advent of MRI, there has been an increase in the detection of these accessory facets. Nevertheless, owing to its small size and unfamiliarity, it is not easily identified. Proper assessment of imaging findings and associated conditions is needed to confirm the diagnosis. Imaging findings in a series of four patients with painful rigid flatfoot revealed the presence of an AALTF with adjacent marrow edema and reduced joint space. This was associated with hindfoot valgus and subfibular impingement. Radiographic suspicion of a non-osseous coalition of AALTF was raised, which was confirmed intraoperatively in one of the patients and demonstrated on CT and MR images in the other patients. This case series presents rare cases of non-osseous coalition of AALTF with a new radiographic sign, the 'reverse tip of the iceberg sign'.

Objective

Five cases of giant cell tumor of bone (GCTB) in the head and neck region were reported, with a main focus on the radiological findings to identify common characteristics for the diagnosis of GCTB in these sites.

Materials and methods

Five consecutive patients diagnosed with GCTB were retrospectively selected. Radiological features on conventional and advanced MR sequences and CT were analyzed. HE staining and immunohistochemical examination were performed using antibodies against p63 and CD68.

Results

The common clinical features were local mass (3/5), tinnitus (3/5) and headache (2/5). Radiologically, all the cases were well-circumscribed osteolytic lesion, majority of cases demonstrated an expansile growth pattern and “soap bubble” appearance on CT (4/5). On MRI, the tumors showed predominantly hypointensity both on T1WI and T2WI, and no evidence of restricted diffusion on DWI. Intratumoral hemorrhage (2/5), cystic alternation (2/5) and very low signal on T2WI in the periphery region of the tumor (4/5) was found. Fluid–fluid level was noted in one case, which was eventually verified to be GCTB with secondary aneurysmal bone cyst (ABC). With contrast agent, all the cases showed striking (3/5) or mild to intermediate (2/5) enhancement.

Conclusions

Although the above described radiological findings are not specific for GCTB in head and neck region, a well-defined osteolytic lesion in the bones of head and neck region with “soap bubble” appearance on CT and hypointensity on T2WI with very low signal in the peripheral region of the tumor on MRI highly suggest GCTB for patient ages 20 to 40.

This narrative review explores recent advancements and applications of modern low-field (≤ 1 Tesla) magnetic resonance imaging (MRI) in musculoskeletal radiology. Historically, high-field MRI systems (1.5 T and 3 T) have been the standard in clinical practice due to superior image resolution and signal-to-noise ratio. However, recent technological advancements in low-field MRI offer promising avenues for musculoskeletal imaging. General principles of low-field MRI systems are being introduced, highlighting their strengths and limitations compared to high-field counterparts. Emphasis is placed on advancements in hardware design, including novel magnet configurations, gradient systems, and radiofrequency coils, which have improved image quality and reduced susceptibility artifacts particularly in musculoskeletal imaging. Different clinical applications of modern low-field MRI in musculoskeletal radiology are being discussed. The diagnostic performance of low-field MRI in diagnosing various musculoskeletal pathologies, such as ligament and tendon injuries, osteoarthritis, and cartilage lesions, is being presented. Moreover, the discussion encompasses the cost-effectiveness and accessibility of low-field MRI systems, making them viable options for imaging centers with limited resources or specific patient populations. From a scientific standpoint, the amount of available data regarding musculoskeletal imaging at low-field strengths is limited and often several decades old. This review will give an insight to the existing literature and summarize our own experiences with a modern low-field MRI system over the last 3 years. In conclusion, the narrative review highlights the potential clinical utility, challenges, and future directions of modern low-field MRI, offering valuable insights for radiologists and healthcare professionals seeking to leverage these advancements in their practice.